Digital vector generator utilizing intensity control as a function of vector angle and velocity

ABSTRACT

An intensity control circuit for use in a high-precision vector generator in which the intensity of the trace on a cathode ray tube is controlled as a function of the angle and speed at which a vector is to be drawn.

United States Patent Granberg et al.

[ 1 Mar. 27, 1973 [58] Field of Search.....3l5/22, l8; 340/324.1, 324 A[56] References Cited UNITED STATES PATENTS 3,325,803 6/1967 Carlock etal. ..315/l8 X 3,333,147 7/1967 Henderson ....340/324 l 3,403,288 9/1968Bradley et a1 ..315/18 X Primary Examiner-Carl D. Quarforth AssistantExaminer-J. M. Potenza Att0rneyThomas J, Nikolai, Charles A. Johnson andJohn P. D ority [57] ABSTRACT An intensity control circuit for use in ahigh-precision vector generator in which the intensity of the trace on acathode ray tube is controlled as a function of the angle and speed atwhich a vector is to be drawn.

1 Claim, 40 Drawing Figures s-loo s-no 5-IOB BUFFER H04 BUFFER s-aa s-veS (FIG. 20)

1 HEA Sax 5.5 5-58 5-60 5-22 S Y [5 1548 com ms. 15) CONTROL 6 POSITIONWORD 5-ll2 5-36 LINE 540 M2 F (FIG, l4) CODE 1 54s ocrmr 5 2s 5 34 5 u eDECODER WORD VECTOR woao [Flam ans L s-ze me. 9) G tNPUT BUFFER PatentedMarch 27, 1973 3,723,802

25 Sheets-Sheet 1 5 2 4 3 3 4 2 5 I .002 3 Ist 0cm. 2nd 0cm. am 0cm.Fig. 20 Fig. 2b Fig. 20

POSITION WORD [F] x posmon Y osmou ||l2----4ls -l4'l5 -24 Fig. 3a Q cP\O%-\,\\\

VECTOR WORD {T TANGENT 0R COTANGENT x OR Yu FlNAL l1 l2 sla --|4||5----24 INVENTORS j MAUR/TZ L. GINA/BERG HUBERT MK MUELLER, JR.

Patented March 27, 1973 3,723,802

25 Sheets-Sheet 3 sax 5'22 S Y FTQ'J'B [COMP (FIG. l5) CONTROL 6POSITION WORD -5-56 5-H2 5-36 LINE '5'40 M2 F (FIG.I4) CODE T 546 OCTANT5-10 6] s oscoosn l (FIG.|0) WORD VECTOR WORD FLAG L 5- 26 J (FIG. 9) G{|NPuT BUFFER (Has) I Patented March 27, 1973 25 Sheets-Sheet 4.

CLOCK GENERATOR fig. 6

T3 I T4 Patented March 27, 1973 23 Sheets-Sheet 9 Patented March 27,1973 215 Sheets-Sheet 12 mokum 5 P2302 2 MA W 10 E 5:08 ov-m BIT 3Patented March 27, 1973 COMPARE VECTOR DRAW I O CYCLE CYCLE STOP CYCLE25 SheetsSheet 14 q GATE To x ,Y AND ocTANT REGISTERS.

02 GATE To T AND F-REGS. AND TO D/A CONVERTER FROM x AND Y.

04 GET DRAW PRESET FLIP-FLOP.

Q CLEAR C-REG.,GATE x ANDY To D/A coNvERTER, sET INTENsITY FLIP-FLOP IFDRAW FLAG FLIP- FLOP sET.

03 SET DRAW FLAG FLIP-FLOP, ENABLE SUBTRACTOR AND COUNTER CYCLE m GATE cTo x OR Y AND s T0 x 0R Y.

0 GATE x AND Y To D/A CONVERTER Q3 GATE TO D AND S-REG.,(OBTA|N comINHIBIT GATE SIGNALS TO D AND s.

0 GATE (2 TO Xu OR Yu AND 5 TD x OR Y, SU STOP FLIP-FLOP.

0 GATE x AND Y To D/A CONVERTER.

0 CLEAR DRAW PRESEL'DRAW, AND INTENSITY FLIP- FLOP OPERATION TIMINGCHART Fig. 23

BEAM BLANKING CONTROL Fig. 25

Patented March 27, 1973 25 Sheets-Sheet 18 on 2: C3050 ZOFDQFPQQ .EwmmnuN mN m mm 9w am OTmN Patented March 27, 1973 25 Sheets-Sheet l9 o- \om\Non m mm mm w m L R mm V QM 5E KDQEU ZOFDmEEmE .rzwmmDo

1. A device for controlling the intensity of a vector drawn on the face of a cathode ray tube by an electron beam, comprising: current metering means including a plurality of semiconductor switches individually connected in series with a resiStor of predetermined value and in parallel with one another; gating means having at least two input terminals and an output terminal; means connecting the output from said gating means to said semiconductor switches such that when said gating means is enabled, individual ones of said semiconductor switches will be rendered conductive; means for applying digital signals representative of the angle at which the vector is to be drawn to one of said two input terminals; and means for applying digital signals representative of the speed at which the vector is to be drawn to the other of said two input terminals. 